Joseph Whitworth and Co
J. Whitworth & Co. of Openshaw, Manchester.
Development of the Business
Note: See the entry for Joseph Whitworth for a detailed account of his life, work, innovations, etc.
1833 Joseph Whitworth rented rooms in Port Street, Manchester, offering his services as a tool-maker. After 5 - 6 months he moved to much larger premises in central Manchester (44 Chorlton Street) . His business went on to manufacture lathes and other machine tools, which were renowned for their high standard of workmanship. In addition, measurement and inspection tools and screw threading equipment were developed and sold.
1834 Approached by John Wilde and together they worked on a patent for a knitting machine
1834 Patent for a machine for turning and screw-cutting.
1834 Advertisement: 'TURNING TO BE LET In a New Building, one Large ROOM, 120 feet long by 40 feet wide, with an attic the same and about eight horse power- Apply on the premises, to Messrs. Joseph Whitworth and Co., Chorlton-street, Portland-street.'
1838 Description and illustration of Whitworth & Co's 'patent case-hardened screw-stock'. Three radial dies were moved inwards by a 'scroll chuck' type of action, controlled by a micrometer screw.. This was soon superseded by his 1842 design. See below.
1838 Correspondence with Boulton and Watt: Prices of Whitworth & Co.’s patent screw stock, planing machines etc. Docketed 'Schedule of prices of their screw lathes and planing machines. Propose calling with drawings and models.'
1841 'The Earthenware Manufacture.— We understand that a machine — the second or third already finished under the direction of the inventor is now completed, and about to be sent from the Messrs. Whitworth & Co., machine makers, Manchester, to the Staffordshire Potteries. This machine, by the application of a power hardly equal to strength of a boy, will mould and prepare for for reception in the pot house, six pieces of ware in one minute, or upwards of 4,500 a day of twelve hours! The work is exceedingly beautiful, and the machine appears fully to answer the purpose of its inventor, Mr. George Wall, who, in connection with Mr. Ridgway, of the Potteries, has obtained a patent for the invention.— Manchester Guardian.'
1842 Description of Whitworth's patented guide screw stock for cutting external threads
1842-3 Correspondence with Boulton & Watt about a lathe supplied by Whitworth 
1843 Mention of a 'very ingenious machine, devised by Mr. Wall, and now in operation at Mr. Whitworth's foundry, at Manchester, by which plates, cups and saucers, and other delf or porcelain articles are made with great accuracy and expedition...'
1845 Made an adjustable pitch propeller. Presented to the London Science Museum in 1858 (Inv. No. 1858-22). Said to be the first actual variable pitch propeller. 5.75 ft dia, blades 2.5 ft wide, pitch variable from 4.75 to 10,75 ft. Made for HMS Dwarf, but never used.
1846 'Messrs. Whitworth and Co., the eminent machinists in Manchester, are now engaged in making a screw propeller for one of her majesty's steam frigates. It is to be made of brass, and will doubtless be the largest casting in that metal that ever took place in the county. That the propeller will be executed in all but an inimitable manner there can be no doubt; and there is little doubt but that Messrs. Whitworth will, in consequence, secure the patronage of the government in at least similar engagements.'
1849 'TO BE LET, Extensive PREMISES, suitable for workshops, stores, or stables, and TWO WHARFS, occupying altogether about 4,000 square yards, extending from Chorlton-steet to Zara-street — Apply to JOSEPH WHITWORTH Chorlton-street, Manchester.'
1849 A 'Bishopp's Disc Steam Engine' was used for driving two Applegarth's printing presses at The Times, made by Messrs Joseph Whitworth. It was a 16 HP high pressure condensing engine, and 'was first tested by Mr Penn of Greenwich in the mill of Mr Farey'. The press produced 5000 complete copies per hour 
1851 Award at the 1851 Great Exhibition. See details at 1851 Great Exhibition: Reports of the Juries: Class VI.
1853 Described as makers of screw-cutting and planing machines 
1857 'VISIT OF PRINCE NAPOLEON TO MANCHESTER.... Nearly an hour was spent in Messrs. Philips's warehouse, the Prince expressing himself very much pleased, and then the party, about two o'clock, proceeded to Messrs. Whitworth and Co.'s engineering works, Chorlton-street. As the party had come without notice, Mr. Whitworth was not present to receive them, but Mr. Hulse, the manager, was at hand, and conducted them through the works. The Prince evinced great interest in the machinery and mechanical appliances, and displayed considerable knowledge of mechanics, as well by the questions he addressed to Mr. Hulse, as by the readiness with which he apprehended what was explained to him. With the rifles, and the large shot for ordnance, he was very much pleased. The clean and orderly appearance of the works also attracted the Prince's attention, and he manifested especial interest in the steam travelling crane in the erecting shop, and the steam crane in the foundry. In Mr. Whitworth's works a full hour was spent, and, on leaving, the Prince signed his name in the visitors' book, "Napoleon, Prince Francais." The party next proceeded to the vulcanised India-rubber works of Messrs. Charles M'lntosh and Co.,....'
1862 Seventeen Whitworth machine tools, plus hand screwing apparatus and internal and external gauges, exhibited at the 1862 International Exhibition in London. . See 1862 London Exhibition: Catalogue: Class 7.: J. Whitworth and Co.
Maker of stationary steam engines.
1866 Report of a works visit in 'Engineering'. There were about 700 employees, and 600 self-acting machine tools. The foundry was approx 220 ft long, with a row of pillar cranes, each worked by its own two-cylinder engine. A planing machine with a capacity of 30 ft by 7 ft was soon to be joined by one of 40 ft by 10 ft capacity. Milling had not found much favour, except for cutting gear teeth and for nut-shaping. However, a large milling machine for armour plates was in the course of construction, for export to France. Particular attention was paid to the production and sharpening of cutting tools for lathes, planers, etc. Tools were forged to shape in dies. One man was employed in grinding between 1700 and 1800 tools per week, using a purpose-made cutter grinder, and finishing with a copper disc and emery powder.
1867 'Whitney [ Baxter D. Whitney ] workmen were always equipped with the best tools available. Mr. Whitney was the first to introduce a radial drill into the United States. This machine was bought from Sir Joseph Whitworth of Manchester, England, in 1867, and it remained in condition to do most creditable work for many decades.'
1867 'THE BELGIAN VOLUNTEERS IN MANCHESTER. Yesterday morning the Belgians were to have paraded in front of the Infirmary at ten o'clock, but they were so tired with their previous day's labour — for it must be remembered that it is labour to be occupied from early morn to late at night visiting place after place — that there was some difficulty in getting even a moderate muster at the Queen's Hotel. Hundreds of people assembled in front of the hotel and the Infirmary, to witness the announced parade, and were somewhat astonished to see the Belgians start down Portland-street about half-past ten o'clock, without there having been any parade at all. The Belgians were preceded by small body of police, and accompanied by some members of the Belgian reception committee. On arriving at the Whitworth Co.'s works, the first thing that struck their attention was a huge 300-pounder lying in the yard. They were then taken into the foundry-room, where the projectiles are manufactured, and were shown the process of casting shells. The erecting shop, which is one of the largest workshops in the city, was next visited, where Allen's engines (an American patent) are made, and Case shot for rifle guns are planed. The immense planing machine — by which huge castings of forty feet in length can be planed— attracted much attention. On going into the turning shop they were hoisted by machinery from the bottom to the top room of the building, catching as they rose long perspectives of the various rooms filled with machinery in motion, which they declared to be jolie. The machines by which Case shot is finished were shown, and sludding [slotting?], and single and double shaping machines. To the question addressed to one of the men what he was making, tbe reply was, "shaping jaws for four screwed chucks," information which left the questioner none the wiser. The store of finished rifles were next visited, where were exhibited shot, shell, and fuses. The small arms manufactory and heavy gun shed were not shown, but the visitors saw enough to be deeply impressed with the ingenious and powerful mechanical appliances for which England still remains pre-eminent, and to which she is in a great measure indebted for her present position among nations.'
1869 Whitworth was created a baronet
1874 Joseph Whitworth and Co was incorporated.
1879 Supplied armour plates for the torpedo ram 'Polyphemus'. 'They will be altogether different from any armour plates yet made, as the material used will be chilled steel.'
1880 The company started a phased move to a new, larger works in Openshaw, Manchester, producing steel, armaments, tools and other engineering products
The company supplied equipment and technology to its competitors at home and abroad, including their massive hydraulic presses and the 'fluid compressed steel' technology (see below). This came to the attention of the US Gun Foundry Board when they visited Europe’s manufacturers in 1883. To quote from pp 14-15 of the Report:- 'In speaking of the Whitworth establishment at Manchester as unique, and of the process of manufacture at that place as a revelation, reference is specially made to the operation of forging. As to the assorting of ores, and the treatment of metal in the furnaces, there is no intention to draw distinctions ; but as to the treatment of the metal after casting there can be no doubt of the superiority of the system adopted by Sir Joseph Whitworth over that of all other manufacturers in the world. 
1884 'LARGE STEEL FORGINGS. Sir Joseph Whitworth and Co., of Manchester, have just completed several exceptionally large steel forgings. One of those is a tube for one of the 110 [ton] breach-loading guns now being built for the Government at Elswick. This tube has a length of 42ft. 6in , outside diameter of 27.1 in., and is made with a forged hole 14 3/4in. diameter. The total weight of the forging sent out of the works is 26 tons, and it is the largest gun tube made in this country. It is a splendid specimen of one Sir Joseph Whitworth's specialities in hollow forging, and if it had been a solid casting it would have been over 40 tons in weight.
Another large forging is a shaft for a new steamboat that being built by Messrs. Laird and Co., of Birkenhead, for the City of Dublin steam packet company, which, it is said, will be the swiftest paddle-wheel steamer ever built. The maximum outside diameter of the shaft is 30 1/2in., minimum 24in., with a hole from 14 to 15in. in diameter; the throw of the crank is 51in., total length 55ft., and total weight 49 tons. This a built-up shaft, forged hollow, which reduces its weight by one-third, as compared with a solid shaft, and it will be finished ready to drop place in the steamship.' 
1888 May. Limited company formed to acquire the undertakings of Joseph Whitworth and Co 
1893 Supplied a 10,000 ton armour plate press to Carnegie Steel, Pittsburgh, along with several hydraulic travelling cranes to lift 120 tons each, and engines and hydraulic pumps. The press’s ram and cylinder weighed 75 and 78 tons respectively. 
Joseph Whitworth embarked on the development of precision measuring machines in 1834. They were produced for sale, and remained in production for many years. For description, see 'The Whitworth Measuring Machine' by Goodeve and Shelley
The company produced vernier calipers,and other portable measuring instruments including James Cocker's 'patent measuring gauge'.
J. Whitworth & Co. produced, for general sale, a wide range of standard gauges for checking length, diameter, thread sizes, etc., against national standards. The benefit of this provision for standardised production cannot be overstated, and large numbers were widely exported.
Examples of Whitworth Machine Tools
An early gear cutting machine is preserved (Science Museum?) but not on display. See photo of photo displayed at Manchester's Museum of Science and Industry. A similar machine was illustrated by Armengaud, and the drawings were reproduced in W. Steeds' book. Steeds gives a date of c.1840. The teeth were cut by a milling cutter (not visible in the photo, but it is on a vertical spindle. The gear blank is mounted on the same horizontal spindle which carries the large gear. The large gear is positioned by the anti-backlash worm gear, whose shaft is turned by the indexed hand crank (seen on the left of the photo) via change gears on the other end of the machine. The milling spindle could be tilted to cut helical gears.
1842 Planing machine on display in the London Science Museum
1842 Planing machine and various other Whitworth machine tools (lathes, shaping machine, drilling machine) in Manchester's Museum of Science and Industry
1842 Screwcutting lathe described and illustrated by Armengaud
1847 Machine tools including patent self-acting slotting machine; radial drilling machine 
1852 Self-acting drilling and boring machine. (Joseph Whitworth and Co of Manchester)
1862 Seventeen Whitworth machine tools, plus hand screwing apparatus and internal and external gauges were exhibited at the 1862 International Exhibition in London. Described and illustrated by D. K. Clark. . See 1862 London Exhibition: Catalogue: Class 7.: J. Whitworth and Co.
1880 'The largest lathe in the world has just been erected at the St Chamond steelworks, in the Department of the Loire. This fine piece of machinery was supplied by Sir Joseph Whitworth and Co., of Manchester, for no French company could be found to supply it at anything like the price, or time of delivery, offered by that firm.' 
1880s planing machine and slotting machine were used until recent times at Bristol's Underfall Yard Workshops, and are now preserved there.
1901 The US magazine 'Machinery' mentioned that the Betts Machine Co in the USA were using a screwcutting lathe of 24" swing, 16 ft between centres, made by Joseph Whitworth and Co 'twenty or thirty years ago' and bought for cutting leadscrews and feed screws, and 'said to be a most excellent tool for this purpose, the lead screw yet being most accurate, even after its years of service.'
In an article in the American Machinist about speeds and feeds of machine tools, Carl G. Barth stated that 'the only machine I found at Bethlehem that revealed a knowledge of a proper progression of speeds were the large lathes built by Whitworth....'
1855 Article on the manufacture of small arms and artillery concerning tests made by Joseph Whitworth 
1860s Guns were produced under the Whitworth name and also under the name of Manchester Ordnance and Rifle Co.
1870 Machinery for moulding rifled projectiles described in 'Engineering'. The machine was 'designed and lately patented by Sir Joseph Whitworth, of Manchester, and expressly intended for the preparation of sand moulds for rifled projectiles. A leading feature in the machine is that by insuring the ramming of a definite quantity of sand in a given space there is insured the same density in every mould and much greater uniformity than when the ramming is effected by hand. Consequently it is possible to produce projectiles constantly to a uniform size, and thus dispense with the operations of planing and shaping the projectiles which were heretofore necessary to make them fit sufficiently accurately to the rifled bore. ..... The whole arrangement is an exceedingly ingenious one.'
1877 Visit of General Grant: 'On Wednesday the ex-president proceeded to Manchester, where he was very warmly received. General Grant was taken first to the machine and artillery works of Sir Joseph Whitworth, in Chorlton-street. A crowd had gathered in the station, and some hearty cheers were given as the general alighted from the train. The general was received at the works by Colonel Dyer and Mr. Leece, two of the directors, and was shown the process of manufacture in the steel ordnance department. An immense loop of red-hot steel was lifted from the furnace and quickly reduced to one half its size by hydraulic compression, so as to fit it for its purpose in breeching a gun. Some air chambers for fish torpedoes, which are being made for the Government, and a 35-ton gun, nearly finished, were also inspected.' 
1884 ' A Big Gun Tube.— Sir Joseph Whitworth and Co., of Manchester, have completed, for one of the 110-ton guns now being built for the Government, a steel tube which is the largest that has ever been made for ordnance purposes. The length of the tube is 42ft. 6in., the outside diameter 27in., and it made of fluid pressed steel, and forged hollow with a hole through 14 3/4in. diameter. The weight of the tube as it is delivered by Sir Joseph Whitworth and Co. is 26 tons, but if had been made in a solid casting it would have exceeded 40 tons.'
1894 'H.M.S. CENTURION. GUNNERY TRIALS. The new and entirely original system of heavy gun mountings and loading gear by Sir Joseph Whitworth and, Company tried on 4th inst. on board Her Majesty's ship Centurion at Portsmouth. The occasion being the first on which the mechanism had been tested under actual service conditions, attracted a great number of professional officers and gunnery experts. .... The trials were conducted by Captain L. A. Beaumont and Lieutenant Tudor, of the Excellent gunnery establishment, the contractors being represented by Mr. Matthews an Mr. Whinfield; ....' 
1895 'CARRIAGE OF A GREAT GUN. To-day will witness a further development of the resources of the Canal and the local industries. A 10-inch breech-loading gun, weighing upwards of 30 tons, will be hauled along the streets by seventeen powerful horses from the works of Sir J. Whitworth and Co. Limited, Openshaw, to the Salford Docks, to be put on board the steamer Romulus, new express line, Manchester to London, for conveyance to Woolwich Arsenal. This will be an interesting experiment, being the heaviest weight ever hauled along the Manchester streets, or lifted at the Docks, and, if successful, will lead to further traffic of this character.'
In 1865 Joseph Whitworth patented a method of improving the quality of steel ingots by subjecting the molten steel to high pressure with the aim of closing up gas pores.
1879 'THE WHITWORTH PATENT.
The Judicial Committee of the Privy Council yesterday extended the patent for manufacturing compressed steel for guns and torpedoes invented by Sir Joseph Whitworth.
'The Government will have the use of the invention without paying the royalty. The evidence of Sir Joseph Whitworth, taken before Mr Henry Reeve, C.B., on the 21st. of July last, was read at length to their Lordships. Sir Joseph, having formally spoken as to the utility and novelty of his invention, deposed that before 1865 no such thing as compressed steel was known in the market. About that time he was engaged in the manufacture of artillery and small arms, and he had been very desirous of obtaining the best quality steel that could be procured for various purposes in his works. Before 1860 there was no getting steel that had the requisite amount of ductility and soundness. Steel of a certain amount of hardness could be got, but not of ductility. For guns, ductility was indispensable ; but when ductility was required air-cells were liable to be formed. He caused a large ingot of steel to be split open in order to examine the character of the metal. He found the upper part of it full of air-cells, and consequently unsound. It was the best steel in the market, the Bessemer steel. From these difficulties he directed his attention to improving the manufacture of steel — in fact he was driven to it.
Before 1865 (the date of the patent) all the rifle barrels at Enfield were made of iron, and as regards ordnance great prejudice against steel existed. Up to that date it was thought steel was unsafe material employ for ordnance, and that was one reason for the difficulty in getting good steel. He himself had confidence in bring able to obtain steel of sound quality for these works by proper and careful manufacture, and he set his mind to it.
For many years he devoted his thoughts to it, and made constant experiments. Before the letters patent were granted he had made at least 2500 experiments. He believed that the use of steel barrels, both for rifled small arms and for rifled guns, was attributable to his adoption of that metal for guns. He knew of no other manufacturer who had advocated the use of steel for firearms.
He compared "Damascus metal." so called, with his own. The former burst with 105 grains charge; the latter did not burst at all. The fluid-compressed steel was thus very much the stronger metal.
His invention consisted practically in employing moulds of steel in which fluid steel was subjected to a very high pressure. Any gases retained in the fluid metal were pressed out, and the particles of the metal were thus forced into the closest possible connection. A pressure of not less than six tons on the square inch was required. The want of steel sufficiently strong to be used with this test delayed his operations for many years. The ordinary steel in the market could not stand the test. At last he made what was known as the 8000-ton press. Before he was able to use his own material (the fluid-compressed steel) the workmen always " bolted" when the pressure was put on, and they ran out of the steel-house for fear of accidents. His invention was also applicable to cast iron, but it was more advantageous to compress steel than cast iron. Compressed steel was made down to 30 tons' strength and 40 per cent, ductility. All below that strength was called " iron."
He had carried on the manufacture of machine tools in Manchester since 1833, and of ordnance since 1859 or 1860. His firm had made rifle barrels from 1857. They also made screw propellers, shafts, and cylinder linings. making the steel propeller shaft the Inflexible by his method a weight of 34 tons was saved, while the strength was' greater. The demand for the fluid-compressed steel was gradually increasing, and accidents had been materially reduced. He had, by publications and other ways, done all could to bring the advantages of his invention before the public, and had been always willing to grant licenses to people using his goods. His company was now constituted that whenever any deserving workman in its employ might desire to take shares and invest his savings he might do so under conditions that were especially advantageous him. It was not until 1869 (four years after the patent was granted) that he was able complete his works and apparatus so as to enable him to produce steel in useful quantities.' 
It was not widely known at the time that, in 1819, James Hollingrake had obtained a patent, No. 4371, for improving copper ingots by compression. The process was applied in the production of copper ingots by the Broughton Copper Co over a period of 20 years. The patent description states: "Hollingrake, James.- 'Casting metallic substances into various forms and shapes with improved closeness and soundness in texture.’ The metal is cast in a suitable mould, and great pressure applied by moveable piston or plugs arranged in any convenient manner, to insure the molten particles being compressed into close contact." Hollingrake's contribution was mentioned by Edward Reynolds in a discussion of the treatment of steel by hydraulic pressure steel at the Institution of Civil Engineers in 1875.. Presumably Joseph Whitworth was aware of the process applied at the Broughton Copper Company.
Considerable controversy arose over the value of Whitworth's process, and there was much public discussion about the merits or otherwise. Many of the participants were rival steelmakers.
Location of the Chorlton Street Works
The factory is identified as a Machine Manufactory on the 1849 O.S. map , the entrance being on Chorlton Street, and two sides were bounded by the Rochdale Canal and a branch thereof. The south eastern side was bounded partly by a canal wharf and partly by the Road & Street Cleansing Company's Yard. The various buildings and yards were served by a narrow gauge railway. The premises also provided a rare glimpse of Shooter's Brook, a short section of this mainly culverted stream remaining uncovered in the works yard.
Goad's Insurance Plans Map No. 50, dated 1893 (updated 1899) shows that a large part of one of the buildings shown on the 1849 map was still standing, but marked as vacant. This was similar in design to a typical local cotton mill of the time, having five floors plus and attic, being relatively narrow with numerous windows to give good natural lighting, and having a steam engine at one end. A number of photographs have been indentified in the Manchester City Council Images Collection which show this building    . A curious feature seen in the 1907 photo is the absence of any windows on the northern end wall. This is probably explained by comparison of the 1849 map, which shows the building to be approx 180 ft long, and the 1899 Goad's plan, which shows a building ~130 ft long. The 50 ft long portion on the 1849 map and missing from Goad's plan is shown as slightly narrower, indicating construction in two different phases. In fact Bancks and Co's Plan of Manchester, 1831 shows a block of ten back-to-back houses occupying the location of 50 ft portion.
The building in the photographs might be taken to be a mill, but there is evidence to suggest that it was purpose built for Whitworth. The site was occupied by Whitworth in 1833, and Bancks and Co's Plan of Manchester, 1831 shows no mill there at that time. Supporting evidence comes from 'The Engineer' in 1856 which said 'The fact of the ground area of the establishment being limited by the vicinity of neighbouring buildings has occasioned the principal workshop to be carried up to a very considerable height' . The article also remarked on the provision of a lift for moving men and materials between floors. Also, note the 1834 advertisement quoted above: 'TURNING TO BE LET In a New Building, one Large ROOM, 120 feet long by 40 feet wide, with an attic the same and about eight horse power....'. This shows that the building was new. 'Turning' referred to the availability of power from lineshafts, appealing to various branches of textile manufacture. It is quite possible that the building was designed such that, if necessary, it could be sold off or rented out as a mill, and in fact the top room was used as a smallware mill by James Smethurst ('For sale by auction .... the Top Room of Messrs. Whitworth and Co.'s Mill, Chorlton-treet, Manchester, in the occupation of Mr. James Smethurst....').
The 1866 report in 'Engineering, referred to above, mentions the foundry being approximately 220 ft long. This indicates changes from the 1849 map, as there are no buildings of that length on the map.
No evidence of the Chorlton Street works remains. The site has long been occupied by a large college building, and a garden has been established, covering the area once occupied by the branch canal, wharf, and the site of the Sackville Street premises of the Manchester Ordnance and Rifle Co. The Rochdale canal, between Canal Street and the former works, has survived.
The following notes refer to the works under the names of Joseph Whitworth & Co and Armstrong, Whitworth.
Although the works was still active within living memory, there seems to be relatively little in the public domain to provide a good picture of the factory or its activities. This, and the following section, aim to rescue some aspects from obscurity.
The engineering works is shown on the 1905 O.S. map. The large North Works (predominantly a steelworks), north of Ashton Old Road, was established later. The 1905 premises were bounded by Whitworth Street to the immediate north, by Ashbury's railway sidings to the south, with Clayton Lane South and Crossley Brothers' Otto Gas Engine Works immediately west, and Bessemer Street and the G.C.R yard immediately to the east. The site was 2300 ft (700m) long and 600 ft (180m) wide.
A plan is available showing the layout of the individual departments in 1905, before construction of the large extension north of North Street.
1883 'Sir Joseph "Whitworth and Co.— Further extensions of these works, which are the largest of their kind in the district, have just been completed. The most important of the extensions is an addition the steel works — the second which has been made within 12 months — of new buildings, 150 ft. long by 50ft. wide, and this section now extends over a covered area of about four acres. The constant enlargement of the steel plant has been necessary to keep abreast with the increasing requirements for the enormous steel tubes which are now used for building the heavy ordnance of the present day. Recently Messrs. Whitworth have turned out steel castings for gun blocks weighing as much as 43 tons, and they have just completed for the English Government finished gun tubes, each weighing 30 tons. They have now in hand the manufacture of material for guns of the largest calibre that have yet been produced, in addition to numerous from foreign governments, including France, Spain, Italy, Brazil, and the United States ranging up to 43 tons in weight. With the additional plant recently put down Messrs. Whitworth will now able to turn out steel castings to 60 tons in weight. In addition to gun material the Whitworth fluid pressed steel is largely used, for propeller and crank shafts, and they have just completed for France a couple of shafts 49ft. in length, forged hollow with a lOin. hole and an outside diameter of 15in. Further additions have been made to the works by the erection of a new shop 150 ft. long 50ft. wide for the joiners and pattern makers, who were previously located in the main building, but the space they occupied is now required for a number of special tools that are being put down. Altogether Messrs. Whitworth's works hare now a covered area of between eight and nine acres and with outbuildings and yards occupy about 17 acres of land.' 
1892 'THE WORKS OF SIR JOSEPH WHITWORTH & CO. "The Engineer" contains an account of certain extensions which are being made of the works Sir Joseph Whitworth and Co., of Openshaw, near Manchester. Other important additions are in progress, and the following particulars will be read with interest :— In the tool department they have put down a new plant of special design, the most noticeable being an enormous horizontal lathe or circular planer, the only large machine tool of its kind this country, and constructed to plane or turn 50ft. diameter. This has been specially designed for taking in large wheels, roller paths, turrets, and barbettes, as well as general work of almost any weight. The machine is also constructed so that a large number of tools can be operated at once, the gear being exceptionally powerful for this purpose. I may add that the representatives of the Russian Government, who were recently over ordering a number of special tools, on seeing this large circular planer, were so struck with its general design and adaptability that they at once ordered a tool of similar design, but of slightly greater range, and this tool is now in hand. In addition to this Messrs. Whitworth have in hand a complete plant of tools for Russia specially designed for gun work, and consisting of powerful boring, turning, and planing machines ; one of them is an ingot boring machine, weighing upwards of 150 tons. Another special order is for United States ; and it significant that, notwithstanding the M'Kinley Tariff, Sir Joseph Whitworth and Co. are making for America a number of milling machines of special design, and intended for work in connection with the manufacture of printing machinery. Amongst other additions to the tool department, which has also been considerably enlarged, is a large machine for taper boring, so that large guns can be put together without the necessity of shrinking the tubes. In the ordnance department several new powerful lathes have been put. down, with 48in. centres, and about 118 tons in weight. A special feature of these lathes is that they are all fixed on one continuous bed, 150 ft. in length, and having enormous power in the headstocks, as they are geared up to to 600 to 1, any of the headstocks can be removed, and work up to the whole length of the bed, if necessary, can be taken in. In this department Messrs. Whitworth are very busy, and have hand an order for 60 sets of gun forgings and an enormous quantity of ammunition for guns, from the smallest size upward, while there are also orders in hand for a large number of gun carriages of a special design, both for home and abroad. Other special work includes several new designs for breech actions in quick-firing guns, the mechanism being designed in one instance for opening with one continuous action, this action being reversed for closing ; and there was also one very ingenious design for closing the breech, and firing by a very simple process. I may add that it is intended to connect the gunshop directly with the forge, making a continuous shop 1,750 ft. in length. In connection with the heavy forgings required for gun construction, a new forging press has been constructed with a working pressure of 6,000 tons, and supplied with a couple of hydraulic cranes, each capable of lifting 100 tons. A new steel foundry has also been put down 600 ft. long by 72ft. span, with two powerful overhead travelling cranes, covering the shop, in addition to which there are a number of steam jib cranes, travelling right through the centre of the shop, numerous side jib cranes for light lifts, and the foundry is open at both ends, so that locomotives can run right through to the other shops. Other recent important additions to the works include an exceptionally large pair of horizontal engines and rolling mills for rolling weldless hoops, flues, and boiler shells of large size, carrying out the principle of rolling boiler rings, such as the one which attracted so much attention at the Manchester Exhibition. A new furnace for annealing castings, after they have left the steel foundry, has also been erected; this furuace being capable taking in work up to 60ft. or 70ft. in length, and it may be added that the firm make a special point of annealing all forgings after leaving the machine, so as to remove all internal strain. A new pit planer for planing 70ft. Long, 12ft. wide, and 12ft. high; thus planing in every direction, is another new tool, and a spacious well lighted drawing office, affording accommodation for 30 or 40 draughtsmen, has also been added to the works.'
1905 'Armour Plate in Manchester. The Manchester City Stipendiary yesterday dismissed a summons issued by the Corporation against Messrs. Armstrong. Whitworth. and Co., charging them with allowing black smoke to be emitted from their works at Openshaw. The case for the defence was that the firm manufactured armour plate, and enormous pressure was necessary roll the huge steel ingots, weighing from forty to fifty tons. It required power from seven boilers, and it was impossible to prevent black smoke. It was stated by Mr. Openshaw, who appeared for the firm, that the work would have be discontinued were an abatement order issued. Otherwise the cost of rolling the plates would be prohibitive, and the employment of about two thousand men would be affected. On those grounds the Stipendiary held the firm was entitled to an exemption under the Act.
1907 'ARMSTRONG-WHITWORTH WORKS EXTENSIONS AT OPENSHAW. An engineering correspondent writes: Sir W. G. Armstrong, Whitworth, and Company Limited, to whom the contract for one of the three new "Dreadnoughts" was awarded by the Admiralty a few weeks ago, are now proceeding with a series of important extensions and improvements at their shipyards and works on Tyneside, and also at the Openshaw Works, Manchester. With the view to the construction there of the heaviest armourclads and cruisers, which the present trend of Naval policy seems to indicate will be adopted in the near future by the great Powers, the Elswick shipyard is now being completely re-modelled.
At Openshaw, Manchester, a new shop of eight bays, 250 ft. by 25ft., is being erected on newly-acquired land in North-street. This shop is for the manufacture of smaller guns, screwing tackle, drills, &c. The armour plate erecting and grinding shops are both being increased by 250 ft. in length, and these extensions are being fitted with four 50-ton cranes of 60ft. span. In the Siemens department at Openshaw another 60-ton steel melting furnace is in course of completion, fitted with an electric charging crane and 60 ton electric travelling crane. Further casting pits are also being laid down for armour-plate work. An additional 12,000-ton casting press has been erected for fluid pressed steel, and here ingots can be cast up to 78in. in diameter and 125 ton in weight. Three additional cementation furnaces provided with trolleys and hydraulic door lifts have just lately been completed at Openshaw. At Openshaw, where now 4,500 men are engaged, employment will, when the extensions there are finished, be found for other 500 hands.' 
1932 'TO BE DISMANTLED
Steelmaking Plants at Openshaw
Messrs. Thos. W. Ward, Ltd., Sheffield, announce that the Siemens steelmaking, heavy engineering, and armament plants at the Armstrong, Whitworth Works, Openshaw, Manchester, are to dismantled. The contract for the work of dismantling the plants, which is probably one of the largest its kind, has been placed with T. W. Ward, Ltd., who will commence operations at once. It is understood that the crucible steel and small tools departments at North Street Works, employing from 600 - 700 men, will still continue to operate.' 
1932 Advertisement: 'COLOSSAL DISMANTLING OF THE GREAT ARMSTRONG WHITWORTH WORKS, OPENSHAW, MANCHESTER
ENGINEERING, ARMOUR PLATE, FORGE, FOUNDRY & STEEL MELTING FLANT; MACHINE TOOLS, MOTORS, BOILERS, PLATES and SUNDRIES OF EVERY DESCRIPTION. BUILDINGS, CRANES, GANTRIES, etc. Extraordinary Low Prices.
THOS- W. WARD Ltd. SHEFFIELD' 
1937 'DEMOLITION GOES TOO QUICKLY
Huge Tank Collapses
Gas pipes were broken and hurtling masonry ploughed way through a thick wall the other side of the road in Bessemer Street, Openshaw, Manchester, when one side of a concrete water tank collapsed during demolition. The tank weighed nearly 1000 tons and had been in the now demolished works of Messrs Armstrong-Whitworths. For a week men had been underpinning this huge concrete and steel structure in readiness for its dismantling. Exceptional care had to be taken, as it measured nearly 100 feet by 40 feet and was nearly a foot thick. Its capacity was 100,000 gallons. Its final downfall was to be accomplished by a. locomotive with long chains attached. Chains were in place, men had been whistled clear of danger, and the engine started its run. Suddenly there was a loud rumble. The huge side of the tank nearest Bessemer Street started to tilt.
Steel girders, blocks of masonry weighing many tons, and great pieces of concrete thundered into the street and smashed everything in their path. A lamppost in Bessemer Street was shattered, masonrv twenty feet high blocked the roadway, and a large hole was made in the carriage and waggon shops of the L.N.E.R. Railway on the opposite side of the street. Men were rushed to the scene and started to cut a way through for traffic. After many hours a path only wide enough for pedestrians to pass with safety had been made, the task of breaking the blocks of concrete proving most difficult. No one was injured in the crash, though there was risk of an explosion when concrete fell on the gas meter house in the railway goods yard. Protective sleepers, however, on the roof, withstood the strain until men could drag the pieces to the ground.'
Accidents at Openshaw
Some examples of accidents, drawn from newspapers, selected for their insight into social history and the methods of working at the factory:-
1884 'Shocking Accident at Sir J. Whitworth's Gunworks. — Yesterday morning a shocking accident happened at Sir Joseph Whitworth's Gunworks, Openshaw, by which Edward Gibbons, aged 29, of 14, Kendal-street, Ashton Old Road, Openshaw, was very severely burnt. He was employed as a labourer at the above works, and was at the time assisting in taking out the plug of a furnace containing liquid steel. By some means the bar was not taken away quickly enough, and the molten metal flew all over him, burning him in a shocking manner. He was at once placed in a cab and conveyed to the Manchester Infirmary, where he lies in a critical state.'
1887 'FATALITY AT AN ENGINEERING WORKS. Mr. S. Smelt, deputy city coroner, held an inquest today, on the body of John Jones, 49, labourer, late of Clayton Lane, Openshaw. The deceased was employed at Sir Joseph Whitworth's works, at Openshaw, and on the afternoon of the 15th inst., he was working at an hydraulic press used for castings, and while thus occupied a quantity of molten steel flew from under the ram, severely burning the deceased about the head and arm. He was temporarily attended by his fellow workmen, and afterwards taken to the Infirmary, where he died from the effects of his injuries yesterday. It was stated that a screen was provided to protect the man working the press, and if the deceased had kept under it he could not have been injured. A verdict of accidental death was returned.'
1889 'John Waterhouse, stoker, aged 25, employed at Sir Joseph Whitworth and Co.'s gun factory, at Openshaw, was yesterday assisting to move two waggons laden with gun barrels, when one of the latter, weighing 30 cwt., fell upon him and crushed him in a terrible manner. He died while being conveyed to the Manchester Infirmary. An inquest was held, and the Jury returned a verdict of Accidental Death.'
1894 'FATAL ACCIDENT AT WHITWORTH'S WORKS. To-day, Mr. Smelt, deputy city coroner, held an inquest on the body of Benjamin Hughes (51), a blacksmith striker, lately living in Wood-street, Openshaw. The deceased was employed at the Whitworth Works, at Openshaw, and on Friday was assisting to work some steel under the steam hammer. Acting under instructions he put a stopper on the anvil by the side of the metal being worked. He then told the man in charge of the hammer to work it but after about half a dozen blows had been struck the stopper suddenly flew out and caught the deceased in the stomach. The man was knocked down and died on Sunday at the Royal Infirmary from shock from the injuries.—A verdict of accidental death was returned.'
1901 'ACCIDENT AT WHITWORTH'S WORKS. A WORKMAN'S CLAIM FOR COMPENSATION. This morning, at the Manchester County Court, before His Honour Judge Parry, Frederick Stockley, a labourer, living in Thomas street, West Gorton, sought to recover compensation for injuries under the Workmen's Compensation Act from Sir W. G. Armstrong, Whitworth, and Co., engineers, Openshaw. Mr. Acton appeared for the applicant, and Mr. Cross for the respondents. The case for the applicant was that in the course of his employment at the respondents' works he was in the habit every evening of visiting one of the slag pits for the purpose of finding if there was any slag which could be removed for cooling in readiness for breaking up on the following day. On November 18th, he was riding on a truck which ran past the slag pits and stepped across the truck to look into the pit when his foot caught in an aperture in the floor and he was thrown violently forward, sustaining an oblique fracture of the bones of the leg. The defence was that the applicant was exceeding his duty in visiting the slag pits, and that he had no business there. Had he been seen there he would have been ordered to leave. His Honour held that the case was absolutely undefended, and foolish as the Workmen's Compensation Act probably was it had never said anything so foolish as would uphold the respondents' contention. If it had done so it would be perfectly useless, because it would mean that every man must get his employment clearly defined and must absolutely refuse to work beyond the terms which were defined. Here a man was doing his best to get his work done and was injured in doing it, and he (the Judge) need hardly say that the view of the Act taken by the respondents as to its bearing on the case did not commend itself to him. There would be an award in favour of the applicant for 13s. 1d. a week (being one-half the amount of his wages) and costs.' 
1906 'MANCHESTER FIRM COMPLIMENTED CORONER'S COMMENT. Yesterday, the Manchester City Coroner, inquiring into the death of John Pickering, plumber's labourer, of Barnabas-street, Clayton, complimented Messrs. Armstrong Whitworth and Co. on the excellent precautions taken to prevent accidents at their works at Openshaw. Pickering's death was attributed to a fall from a ladder which he ascended in defiance of a rule that no one was to climb it after dark. The Coroner commented on the fact that though between four and five thousand men were employed at the works, this was only the second fatality in the three years since he came to Manchester. He considered that this proportion, which was quite unusual, was a testimonial for the firm.
1907 'EXPLOSION IN THE SCRAP. MAN KILLED TO-DAY AT MANCHESTER. Two Workers Injured. A serious explosion occurred at the works of Armstrong, Whitworth, & Co., Openshaw, Manchester, this afternoon, resulting in the death of man named Harry Walker and severe injuries to two other men. The men were engaged removing a waggon containing scrap steel, which had been blown to pieces by means of explosives when the explosion occurred. It supposed that a portion of the undischarged explosive was amongst the scrap.'
1914 'FATAL MACHINE ACCIDENT. A verdict of accidental death was returned at an inquest held by the City Coroner (Mr. E. A. Gibson) this afternoon on Charles Farrell (36), Orme-street, Beswick, labourer, who was killed at the works of Armstrong, Whitworth and Co., Openshaw, early on Saturday morning. Farrell was working on a slotting machine in the armour-plate department, and as the table of the machine, on which a large armour plate was placed, was being moved, Farrell put in the ratchet. He did this before he should have done, and the ratchet flying out struck him the head. He died almost immediately.' 
Sources of Information
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- Worcester Journal - Thursday 12th July 1849
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-  'Engineering' 14 Dec 1866, pp.445-6
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- Manchester Courier and Lancashire General Advertiser - Thursday 25 July 1867
- Globe - Tuesday 16 September 1879
- Report of the Gun Foundry Board, 1884
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- The Engineer, October 20, 1893
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- Engineer and Machinist's Assistant 1847. p195 and others with illustrations XLIV
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-  Manchester City Council Images Collection photograph m01695, showing view from Chorlton Street along canal towards Sackville Street in 1907
-  Manchester City Council Images Collection photograph m00714 taken from Canal Street, identified as 'Education Committee Property' in 1907
-  Manchester City Council Images Collection photograph m05583 taken from Sackville Street in 1902, showing the surviving Whitworth building, with truncated chimney and remains of boiler house
-  Manchester City Council Images Collection 'Search' page
- 'The Engineer' 6th June 1856
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- Manchester Evening News, Monday 13th July 1914